Electric elevator.



l0. 7"],625. Patented Oct. 7, I902.

R. C. SMITH. ELECTRIC ELEVATOR.

(Application filed July 10, 1899.) v (No llodel.) 2 Sheets-Sheet I.

-Qifii N0. 7I0,625. Patented Oct. 7, I902..

B. B. SMITH.

ELECTRIC ELEVATOR.

(Application filed July 19, 1899.)

(No Model.) 2 Shets-Sheet 2.

awv auto z wwwii Wih-woae a UNiTnn STATES PA TENT OFFICE.

RUDOLPH C. SMITH, OF YONKERS, NEYV YORK, ASSIGNOR TO OTIS ELEVATOR COMPANY, OF EAST ORANGE, NEW JERSEY, A CORPO- RATION OF NEW JERSEY.

I ELECTRIC ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 710,625, dated October '7, 1902.

Application filed July 10. 1899. Serial No. 723,299. (No model.)

To (all whom it may concern.-

Be itknown that I, RUDOLPH QSmrrn-a citizen of the United States, residing at Yonkers, in the county of Westchester, in the State of New York, have invented certain new and useful Improvements in Electric Elevators, of which the following; is a specification.

My invention relates to that class of elevator apparatus in which the car is connected by flexible suspensories to a counterbalanceweight, so as to sustain the weight of the car and counterbalance on a heavy sheavewheel; and my invention consists in the combination of the motor, an endless drivingrope to move the load or part of the load and the elevator-car in such manner as to move, stop, or reverse the car while the endless driving-rope is constantly running in one direction and takes only the unbalanced part of the load and the cage.

Figure 1 is an elevation illustrating sufficient detail of an elevator to show my improvement. Fig. 2 is an end elevation showing the arrangement and run of the drivingrope and its connection to the car and balance-weight.

The electric motor is placed on a suitable bed-plate on a foundation of proper weight to stand the pull exerted by the driving-rope. Three stands 2 2 2 carry the armature-shaft 3. To this armature-shaft are keyed, properly insulated therefrom, two armatures 4 and 5. The field-coils 6 6 of the armature 4 are attached, by means of the arms 7 7, to a rotary sleeve 8. This sleeve is fitted loosely to the armature-shaft to rotate with the fieldcoils on the shaft 3. On the end of the sleeve 8 is firmly keyed and fitted a driving-wheel 9, grooved to afford suflicient friction to impart motion to one loop of the driving-rope 1O 10. To the armature-shaft 3 is keyed and fitted a similarly-grooved Wheel 11, which takes the other driving-loop of the endless rope.

The rotary sleeve and the journals supporting the armature-shaft are of course fitted with proper lubricating appliances to afford continuouslubrication. Thefield-coilsof the armature 5 are supported in the regular manner on the bed-plate 1. All these field-coils are wound in shunt and are so arranged that the relative motion of rotary field-coils 6 6 and the speed of the armature belonging to the stationary field-coils is quite slow when the full magnetization of the field is used, but to be able to rotate faster when the proper field is weakened by throwing in resistances into the field-circuit, as is well known in the art and needs no special description.

The car 14 and counterbalance 15 are connected by a multiplicity of ropes, and their weights are carried on a sheave 13. The endless driving-rope loop which hugs sheave 11 runs with side 16 around the loose sheave 19 at the bottom of the car and with the other side 17 around the loose sheave 18 at the bottom of the balance-weights and then down to form the loop 10 around the other motor friction-wheel 9. The loose sheaves 18 and 19 are connected with self-adjusting tighteners, which may be with springs or equivalent weights.

The control of the field-coils may be from a properswitch in the car or from the landings.

The circuits by which the field-coils may be strengthened or weakened are led, respectively, from the insulated collars 20 21 by means of brushes and their terminals 22 and 23 t0 the plus and minus supply terminals 24c 25, situated at half of the distance of the rise of the car in the elevator-shaft and from there by means of a proper flexible insulated cable to a switch in the car. This switch is provided with contact-points and the proper resistances connected to the same and contact-brushes to admit more or less current to the field-coils. The circuit of the stationary fields is led in a similar manner from the field-terminals to a switch in the car and from the terminals 26 of the switch in the car to the supply-terminals 2e and 25, situated at half the height of the rise of the car, as described before. Both armatures are connected to the supply-mains, as is customary with shunt-motors, with the proper startingrheostat 27 28 for each armature.

The operation and control of the elevatorcar is effected as follows: The circuits sup plying the field-coils are closed first when starting the apparatus. Then the current is admitted in the usual way to the armatures, which will now rotate with speeds controlled by the manipulation of the fields. Assuming that the armatures received the supplycurrent so as to run in clockwise rotation, the rotary field and its sleeve with a frictionwheel will run in the opposite direction. It is evident that by manipulating the fields shaft and sleeve can be made to run the same number of revolutions, but opposite, as described, since strengthening the stationary field and weakening the rotary field will increase the speed of the rotary field and strengthening the rotary field and weakening the stationary field will increase the number of the revolutions of the armature-shaft. In this case when the number of revolutions of armature-shaft and those of the sleeve are equal as much of the driving-cable would be paid out by one driving-wheel as taken in by the other and the car would stand still. To make the car ascend or descend, the fields must be manipulated to make the proper difference in the number of revolutions of the sleeve and its wheel and of the shaft and of the driving-wheel fastened to the same.

I am aware that the means of controlling the motion of an elevator-car by the difference of the circumferential speed of the driving-pulleys is old, being an invention of Ethelbert Fraser and described in United States Patent No. 616,096. I am also aware that the method of regulating the speed of the motor by means of the two armatures on one shaft, where the driving power is either taken from the rotary sleeve alone or from the armatureshaft alone, is the invention of somebody else.

Without limiting myself to the precise con struction and arrangements of parts shown, I claim 1. The combination of a motor having armature and field capable of opposite rotation, a driving-pulley associated with the armature, a driving-pulley associated with the field and means for maintaining the opposite rotation of the armature and field at different speed ratios, substantially as set forth.

2. In an elevator, a cage, a counterweight, two electric motors and two parallel driving- Wheels rotating about the same axis, in combination with a continuous rope engaging both wheels, and pulleys on the cage and counterweight engaged by loops of the rope, substantially as described.

3. In an elevator, a cage, a counterweight, two electric motors and two parallel drivingwheels rotating about the same axis, in combination with a continuous rope engaging both wheels, and pulleys on the cage and counterweight engaged by loops of the rope, and means for varying the speed of the two wheels, substantially as set forth.

4. The combination with the cage and counterweight of an elevator, of two motors each having an armature rotating about the same axis, one of the fields fixed and the other rotating about its armature, drive-wheels connected to be driven one by the armature-shaft and the other by the movable field, anda continuous rope engaging both wheels and. having loops engaging pulleys on the cage and counterweight, substantially as set forth.

5. The combination with the cage and counterweight of an elevator, of two motors each having an armature rotating about the same axis, one of the fields fixed and the other rotating aboutzits armature, drive-wheels connected to be driven one by the armature-shaft and the other by the movable field, and a continuous rope engaging both wheels and having loops engaging pulleys on the cage and counterweight, and means for varying the speed of the two wheels, substantially as set forth.

6. The combination with the endless-rope drive of an elevator, of two drive-wheels and two motors, one of said motors having a fixed field, and the other a movable field connected to rotate one of the drive-wheels, the armatures of both motors on a shaft connected to drive the other wheel, substantially as set forth.

7. The combination with the endless-rope drive of an elevator, of two drive-wheels and two motors, one of said motors having a fixed field, and the other a movable field connected to rotate one of the drive-wheels, the armatures of both motors on a shaft connected to drive the other wheel, and means for varying the speed of the two wheels, substantially as set forth.

8. The combination of a motor having armature and field capable of opposite rotation, a d riving-pulley associated with the armature, a driving-pulley associated with the field, and electrically-controlled means for maintaining the opposite rotation of the armature and field at difierent speed rates, substantially as described.

9. The combination with two independent, driven pulleys each in constant working connection with a part to be operated, of a motor having a field and an armature mounted to turn in opposite directions, and each connected to turn one of said pulleys, substantially as set forth.

10. The combination with two independent, driven pulleys each in constant connection with a part to be operated, of a motor having a field and an armature mounted to turn in opposite directions, and each connected to turn one of said pulleys, and means whereby the speed of the two pulleys may be Varied and then maintained at any desired ratio, substantially as set forth.

11. The combination with two independent, driven pulleys, and connections between the same and a part to be moved whereby the latter may be driven in opposite directions, of a motor having an armature and a field mounted to turn in opposite directions, and each connected to independently rotate one of said pulleys, and means for varying the speed ratics of the field and armature, substantially as set forth.

12. The combination with two independent, driven pulleys, and connections between the same and a part to be moved whereby the latter may be driven in opposite directions, of a motor having an armature and a field mounted to turn in opposite directions and connected to rotate said pulleys in opposite directions, and means for varying the speed ratios of the field and armature, substantially as set forth.

13. The combination of two independent pulleys, a cable passing" around the same and RUDOLPH 0. SMITH.

\Vitnesses:

H. R. MARsDEN, W. H. BRADY. 

